illumination

American  

[ih-loo-muh-ney-shuhn] / ɪˌlu məˈneɪ ʃən /

noun

1. an act or instance of illuminating.

2. the fact or condition of being illuminated.

3. a decoration of lights, usually colored lights.

4. Sometimes illuminations. an entertainment, display, or celebration using lights as a major feature or decoration.

5. intellectual or spiritual enlightenment.

   Synonyms:

   wisdom, insight, revelation, knowledge

6. Also called illuminance.  Also called intensity of illumination.  Optics. the intensity of light falling at a given place on a lighted surface; the luminous flux incident per unit area, expressed in lumens per unit of area.

7. a supply of light.

   a source of illumination.

8. decoration of a manuscript or book with a painted design in color, gold, etc.

9. a design used in such decoration.

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illumination British  

/ ɪˌluːmɪˈneɪʃən /

noun

1. the act of illuminating or the state of being illuminated

2. a source of light

3. (often plural) a light or lights, esp coloured lights, used as decoration in streets, parks, etc

4. spiritual or intellectual enlightenment; insight or understanding

5. the act of making understood; clarification

6. decoration in colours, gold, or silver used on some manuscripts or printed works

7. physics another name (not in technical usage) for illuminance

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Other Word Forms

• illuminational adjective
• nonillumination noun
• preillumination noun
• reillumination noun

Etymology

Origin of illumination

First recorded in 1300–50; Middle English, from Medieval Latin illūminātiōn-, stem of illūminātiō “spiritual enlightenment,” from Latin: “illustriousness, glory”; see illuminate ( def. ), -ion ( def. )

Explanation

Illumination is light. Kids up past their bedtimes have been known to read entire books under their covers using only the illumination from a flashlight. Use the noun illumination to talk about light, like the illumination of the moon on the surface of a lake. Illumination can also refer to an understanding or a spiritual awareness, like when a mystery of your faith suddenly makes sense to you. The Latin root is illuminationem, "throw into light" — you can picture the light bulb over a person's head in a cartoon to remember the various meaning of illumination.

Example Sentences

Even Apollo astronauts didn't see the Orientale basin completely because of their orbit and illumination conditions.

From BBC • Apr. 5, 2026

Light programmable colloidal crystals may eventually enable reconfigurable optical coatings, adaptive sensors, and next generation display and data storage technologies, where patterns and functions are defined dynamically by illumination rather than fixed during manufacturing.

From Science Daily • Mar. 2, 2026

When the sun vanishes early and the chill of darkness comes on deep and fast, there has always been an instinct to gather around a source of warmth and illumination for tales of fearsome happenings.

From Los Angeles Times • Dec. 23, 2025

Owenna Griffiths, editor of Today, said: "In a rapidly changing world, this year's guest editors will help bring illumination and understanding".

From BBC • Nov. 23, 2025

The illumination from the lamps accompanied the fading sunlight, while the slight angle of the lamplight created soft shadows across his subjects.

From "Shooting Kabul" by N. H. Senzai

Related Words

• brightness